title: A mid-term analysis suggests ceramic on ceramic hip arthroplasty is durable with minimal wear and low risk of squeak.
abstract: BACKGROUND
  The incidence of hip replacements in the younger patient is ever increasing. With this in mind, improving the longevity of hip arthroplasties is paramount. Alumina ceramic is a promising bearing surface due to its low wear rate and biological inertness.
  
  
  OBJECTIVE
  This study aims to review our experience with ceramic-on-ceramic total hip arthroplasty, reporting on the need for revision as well as the cause of failure. Our secondary purpose is to review our experience with the phenomenon of squeaking analysing and its effect on clinical outcome with specific emphasis on component positioning. Also reported are the results of our retrieval analysis of explanted components documenting the wear rate and our analysis of strip wear.
  
  
  METHODS
  A consecutive series of 301 primary cementless alumina-on-alumina total hip arthroplasties at a minimum of 10 years follow-up was reviewed. These arthroplasties all had third-generation ceramic-on-ceramic bearings performed through a posterior approach with repair of capsule and external rotators to bone. We analysed hips both clinically and radiographically. Analysis of wear in 62 ceramic bearings was performed using a Roundtest RA300 machine (Mitutoyo; Andover, UK), which has an accuracy of 0.01 μm.
  
  
  RESULTS
  Overall, the survival rate of the implants was 98% at 10 years. No ceramic fractures were encountered in this study. Seventy-four patients reported squeaking hips, and two cases were revised due to squeaking (0.6%). No failures were related to bearing wear.
  
  
  CONCLUSIONS
  We believe that ceramic-on-ceramic is a safe bearing coupling with excellent survivorship at 10 years.
authors.affiliation: Sydney Hip and Knee Surgeons, North Sydney, New South Wales Australia.
authors.forename: Dennis
authors.initials: D
authors.lastname: Molloy
authors.forename: Chris
authors.initials: C
authors.lastname: Jack
authors.forename: Christina
authors.initials: C
authors.lastname: Esposito
authors.forename: William L
authors.initials: WL
authors.lastname: Walter
keywords: alumina; alumina fracture; ceramic-on-ceramic; review; squeaking